precision highp float; uniform vec2 resolution; uniform float time; uniform vec2 mouse; uniform sampler2D backbuffer; #define PI 3.14159265356 float hash(vec2 p){ return fract(45611.73561 * sin(dot(p,vec2(12.637,78.156)))); } vec3 hash3(vec2 p){ return vec3(hash(p),hash(p + vec2(1.0)),hash(p + vec2(2.0))); } float noise(vec2 p){ vec2 i = floor(p); vec2 f = fract(p); float a0 = hash(i + vec2(0.0,0.0)); float a1 = hash(i + vec2(1.0,0.0)); float a2 = hash(i + vec2(0.0,1.0)); float a3 = hash(i + vec2(1.0,1.0)); vec2 u = f * f * (3.0 - 2.0 * f); return mix(mix(a0,a1,u.x),mix(a2,a3,u.x),u.y); } float fbm(vec2 p){ float n = 0.0; float a = 0.5; float f = 2.0; for(int i = 0; i < 3; i++){ n += noise(p) * a; p *= f; a *= 0.5; } return n; } mat2 rot(float a){ float c = cos(a),s = sin(a); return mat2(c,s,-s,c); } float sdBox(vec3 p, vec3 s){ vec3 d = abs(p) - s; return length(max(d,0.0)) + min(max(d.x,max(d.y,d.z)),0.0); } float sdMebius(vec3 p, float r, float s, float a){ float th = atan(p.y,p.x); p.xy *= rot(th); p.x -= r; p.xz *= rot(th * a); vec2 d = abs(p.xz) - s; return length(max(d,vec2(0.0))) + min(max(d.x,d.y),0.0); } vec2 opU(vec2 d0, vec2 d1){ return d0.x < d1.x ? d0 : d1; } vec2 map(vec3 p){ vec3 p1 = p; p.xy *= rot(p.z); vec3 p0 = p; p0 = mod(p0,2.0) - 1.0; p.xy *= rot(-time * 0.5); vec2 d = vec2(0.0); float s = 1.0; for(int i = 0; i < 5; i++){ vec3 q = mod(p * s,2.0) - 1.0; s *= 3.0; vec3 r = abs(1.0 - 3.0 * abs(q)); float dz = max(r.x,r.y); float dx = max(r.y,r.z); float dy = max(r.x,r.z); float c = (min(dz,min(dx,dy)) - 1.0)/s; d.x = max(d.x,c); } p1.xy *= rot(time * 2.0); p1.z += 3.0 - time; p1.xz *= rot(time * 2.0); vec2 d0 = vec2(sdMebius(p1,0.075,0.025,1.0),1.0); d = opU(d,d0); vec2 d1 = vec2(length(p1) - 0.01,1.0); d= opU(d,d1); return d; } vec3 normal(vec3 p){ vec2 d = vec2(0.0015,0.0); return normalize(vec3(map(p + d.xyy).x - map(p - d.xyy).x, map(p + d.yxy).x - map(p - d.yxy).x, map(p + d.yyx).x - map(p - d.yyx).x)); } float shadow(vec3 ro, vec3 rd){ float t = 0.0; float r = 1.0; float sc = 0.9; vec3 p = ro; for(int i = 0; i < 36; i++){ t = map(p).x; if(t < 0.001)break; r = min(r, t * 32.0/0.001); p += rd * t; } return 1.0 - sc + r * sc; } vec2 trace(vec3 ro, vec3 rd, out vec3 pos, out int steps){ vec2 t = vec2(0.0); vec3 p = ro; for(int i = 0; i < 64; i++){ steps = i; t = map(p); if(abs(t.x) < 0.001){ break; } p += t.x * rd; } pos = p; return t; } vec3 getColor(in vec3 ro,in vec3 rd, out vec3 pos, out vec3 n,out float smoothness, inout float hit){ vec3 col = vec3(0.0); int steps = 0; vec2 t = trace(ro,rd,pos,steps); if(abs(t.x) < 0.001){ vec3 lp = vec3(1.0,0.0,1.0); lp = normalize(lp); n = normal(pos); float s = shadow(pos + n * 0.01,lp); float ndl = max(dot(n,lp),0.0) * 0.5 + 0.5; col = t.y < 0.5 ? vec3(0.3) : vec3(1.0); float ao = 1.0 - float(steps)/64.0; col *= ao * s * ndl; hit = 1.0; if(t.y < 0.5){ smoothness = 0.0; col += smoothstep(0.0,0.25,fract(pos.z + time)) * smoothstep(0.3,0.05,fract(pos.z+ time)); } else { smoothness = 1.0; } } return col; } void main(void) { vec2 uv = (gl_FragCoord.xy * 2.0 - resolution.xy)/min(resolution.x,resolution.y); uv *= 0.25; // Camera Settings vec3 ro = vec3(0.0,0.0,-5.0 + time); ro += (hash3(vec2(floor(time))) - 0.5) * vec3(0.125,0.125,1.0) + vec3(0.0,0.0,5.0); float ti = time * 3.0; float r = 0.125; vec3 lookat = vec3(0.0,0.0,0.0 + time); lookat.xy = vec2(fbm(vec2(time)),fbm(vec2(time))) * 0.05; vec3 cup = normalize(vec3(0.0,1.0,0.0)); vec3 cdir = normalize(lookat - ro); vec3 cside = cross(cup,cdir); float depth = 1.0; vec3 rd = cside * uv.x + cup *uv.y + cdir * depth; rd = normalize(rd); vec3 col = vec3(0.0); vec3 pos,n; float hit = 1.0; float smoothness = 0.0; col += getColor(ro,rd,pos,n,smoothness,hit); vec3 pos0 = pos; vec3 ro0 = ro; // Reflect float a = 1.0; for(int i = 0; i < 3; i++){ ro = pos + n * 0.001; rd = reflect(rd,n); a *= 0.5; col +=a * getColor(ro,rd,pos,n,smoothness,hit) * smoothness; if(hit < 1.0)break; } col = clamp(col,0.0,1.0); // Fog col = mix(col,vec3(1.0),pow(length(pos0 - ro0)/5.0,2.0)); gl_FragColor = vec4(col,1.0); }

Menger Sponge Tunnel